{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"3ef1a7d956816fc497d8fa2a8c65185c8b7cd508ea4edcc525e8177f0501302c","created":"2026-10-03T07:18:04Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"8831fc768059a45049c162ca18ce313915cf0c80bb5c4670e8eebd349d3b1212","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"fluid.turbulent-combustion.cell-size-prediction","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"The front of a gas detonation is a pattern of crossing shock waves that scratches a fish-scale pattern on a sooted wall, and the width of these cells decides whether a detonation can pass through a pipe or an opening. At present the width can only be estimated from chemistry to within a factor of a few.","posed_since":"","precise":"For gaseous detonations (H2-O2-Ar, H2-air, hydrocarbon-air) at initial pressure $p_0$ and temperature $T_0$, predict the mean cell width $\\lambda$ from the detailed chemical mechanism. Empirical correlations $\\lambda = A \\Delta_I$, with $\\Delta_I$ the induction length of the one-dimensional steady detonation, need $A$ between about 10 and 50 depending on mixture. An answer predicts $\\lambda$ within 20 percent across mixtures and initial conditions with no fitted $A$.","problem_ref":null,"references":"","settled_by":"Three-dimensional resolved simulations with validated chemistry, or a reduced theory, that reproduce measured cell widths for several mixtures and pressures without mixture-specific tuning.","status_note":"","title":"First-principles prediction of detonation cell size from mixture chemistry","topic_ref":"ff8822779d7d3829d62f794eaee78060074a7c7c5588960c0eae974a587339ac"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"ad5938a0aee96c1c52b1e3ab566b6d801fbef9a2b31785693cd7b83167cbddb8","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"c35e78453169325344648b2b0a196e9e3c7c7dba436f6f418509c18cfeecbbdf","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"qj6w2iWM5s7WQZoSrZaUYYSeWmH30Lm0fvBGx8jjuMCNtjDAjb8x694fLPM8wuJN2MA4wHIzdQY1OGSnNlCZDQ"},"schema":"pubphys.envelope/1"},"record_hash":"ad5938a0aee96c1c52b1e3ab566b6d801fbef9a2b31785693cd7b83167cbddb8","leaf_index":1446}